Chicago Public Schools mistakenly told hundreds of families that their children had won a coveted spot at a marquee North Side school this week — then had to quickly retract the offer.

Only 16 spots were available at the LaSalle Elementary magnet school campus in the Old Town Triangle neighborhood. But CPS said it issued 512 offer letters to families that had applied to enter LaSalle's first through eighth grades.

An unidentified "internal error" in assigning transfer students to the campus sparked the problem, CPS said.

"When the error was discovered, CPS immediately called and emailed all families that received an incorrect notification," CPS spokesman Michael Passman said in a statement. "District staff is working with families individually to help identify alternate options for their children."

The mistake illustrates the frustrations of many city parents faced with the pressure-cooker environment built around gaining access to Chicago selective public school programs.

"It really is a beat-down, this process," said Wendy Donahue, an Old Town neighborhood resident who heard Monday that her 9-year-old's offer to attend LaSalle was withdrawn.

"It's just a confounding process, there's got to be a better way," said Donahue, a former Tribune reporter and editor.

Donahue said she applied to six other magnet schools, and has gone through the process without success during the course of the past few years. Fortunately, Donahue said, her daughter already attends a private school the family is happy with.

Hundreds of students mistakenly received letters of acceptance to LaSalle Elementary magnet school before Chicago Public Schools officials retracted the offers. April 5, 2016. (CBS Chicago)

Hundreds of students mistakenly received letters of acceptance to LaSalle Elementary magnet school before Chicago Public Schools officials retracted the offers. April 5, 2016. (CBS Chicago)

Affected families were to receive phone calls from CPS officials to discuss their options. That can get complicated for families that may have rejected offers from other schools, though CPS said it would work with parents to "reinstate those offers."

"I am deeply sorry to have to inform you of this change," CPS admissions official Kathryn Ellis said in a message distributed to affected households.

"The application and enrollment process is an emotional time for many families, and I want to assure you that we will work individually with your family to make sure you understand your options," Ellis said.

Chicago Public Schools said kindergarten offers for LaSalle were not affected by the error, and that LaSalle was the only school affected.

Applicants to LaSalle are selected by a computerized lottery, though priority is given to applicants who have a sibling enrolled. The district says that after students' siblings are "accommodated," 40 percent of the remaining seats are doled out to applicants who live within 1.5 miles of the school.

A version of this article appeared in print on April 06, 2016, in the News section of the Chicago Tribune with the headline "CPS retracts magnet school acceptances" —
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